trxcon/l1sched: transmit dummy speech blocks with inverted CRC3
In case when an Uplink TCH/[FH]S frame needs to be transmitted, but
there is no frame available in the Tx queue, transmit an intentionally
invalid block with inverted CRC3. This will induce a BFI condition in
the BTS side receiver. See also the related osmo-bts-trx patch.
Change-Id: I16ff09a220da13c2c76538bc43354afc4e688794
Depends: libosmocore.git Iade3310e16b906efb6892d28f474a0d15204e861
Related: osmo-bts.git I78106802a0aa4af39859c75d29fe0e77037899fe